External tire pressure gauges have been used widely the fundamental principle underlying which involves an external sensor installed on the wheel hub of a tire. Said sensor includes a bridge electronic gas pressure sensing device for sensing gas pressure. It transforms gas pressure signal into electric signal and transmits the signal to a receiver through a radio transmitter device. Kinds of data changes may be displayed on a screen of the receiver. Or, they may take form of buzzing to remind the driver. In addition, in case that tire gas leakage occurs and pressure change exceeds a safe threshold, alter will be generated for ensuring safe driving.
Normally, the display of tire status and alerting device are disposed on the front console of the cab and are coupled with a car battery by a connecting line so as to be powered. This kind of devices and their connecting lines occupy space of the cab. Moreover, these connecting lines may be accidently touched by the driver. Furthermore, instruments on the front console of the cab may divert attention of the driver and thus result in bad influence on safe driving of the car. To make improvement, many solutions have been proposed in related industry to integrate tire pressure monitor function into the car console. The present applicant has also proposed implementation of tire pressure monitor by getting power from the car cigarette lighter receptacle. However, the former solution causes heavy cost and therefore is not suitable for car products available in the marketplace. The latter one occupies the cigarette lighter receptacle of the car and is not convenient for the driver to use other display devices.
In detail, according to the applicant's solution where power is obtained from the car cigarette lighter receptacle, the indicator and its power getting plug are integral. The indicator is basically perpendicular to an axis direction of the plug of the cigarette lighter receptacle and is fixed onto the same element. This causes some shortcomings.
At first, as the indicator is fixedly connected to the plug, it can present data to the user only from one angle thus lacking flexibility. In this situation, the user is limited to read displayed data in the visual range of the indicator.
Secondly, as the indicator is fixedly connected to the plug and the indicator uses relatively large space, indicators of the same size will not certainly be suitable for cars with different console streamline design. Moreover, use of space around the power getting receptacle may also be influenced, hence influencing manipulation of the driver. For example, this may possibly obstruct pushing action of the gear levers.
Thirdly, once one or two power getting receptacles on the car are occupied by the indicator, it will be impossible to provide power receptacle for other devices. Apparently, this kind of resource use lacks of efficiency.